French President François Hollande announced on Friday that France would not be paying reparations for the role of the state-owned CDC bank in the slave trade, despite allegations that a €21 billion debt has crippled Haiti for centuries.

Hollande on Friday ruled out the payment of reparations for slavery as a rights group announced a suit against state-owned bank CDC over its role in the trade.

"What has been, has been," Hollande said in a speech to mark France's slavery remembrance day. "History cannot be rubbed out. It cannot be subjected to an accounting process that... would be impossible to complete."

France's Representative Council of Black Associations (CRAN) announced it will on Monday be serving a writ on the bank CDC (Caisse des depots) over its role in the slave trade in general and events surrounding Haitian independence in particular.

"The CDC was an accomplice to a crime against humanity," CRAN President Louis-Georges Tin told reporters. "It played a considerable role in the slave trade."

Haiti won its independence from France in 1804 after the celebrated slave revolt that had been inspired by the French revolution of 1789.

But the French navy subsequently blockaded the Caribbean country and extracted massive compensation for the colonial power's property losses.

According to Tin, the amounts paid to France via the CDC between 1825 and 1946 were the equivalent of $21 billion in today's money and contributed to a legacy of underdevelopment that has left Haiti as one of the poorest countries on the planet.

"This ransom condemned Haiti to an infernal spiral of instability and misery," he added.

Legal experts believe that CRAN's action has little prospect of making headway through the French courts, with even the organisation's own lawyer, Norbert Tricaud, implicitly admitting as much.

"If we are presenting this suit, it is to promote debate," Tricaud said.

In the United States, a class action aimed at forcing the bank JP Morgan and 17 other companies to pay reparations for their involvement in slavery was dismissed in 2004.

JP Morgan subsequently issued a public apology over the action of two of its predecessor banks, which had accepted slaves as collateral on loans.

The bank also agreed to set up a $5 million scholarship fund to help with young blacks from poor backgrounds with education costs.